1. Field of the Invention
The present invention relates to a retractor device for a seatbelt that can wind a seatbelt and a seatbelt device having the same.
2. Description of the Related Art
A seatbelt device provided on a seat of a vehicle generally has a retractor device for a seatbelt which winds one side of a seatbelt (webbing) capable of being extracted, a tongue provided at the seatbelt, and a buckle device for causing an occupant to wear the seatbelt.
The retractor device for a seatbelt retracts the seatbelt inside by winding it around a winding member (spool) by using a spring force, locks extracting of the seatbelt from the winding member at a collision when an impact acts, and restrains the body of the occupant who is rapidly moving forward with this locked seatbelt. At this time, since the occupant moving forward is rapidly restrained, a load by a reaction of the restraint acts on the chest part or the like of the occupant through the seatbelt. In order to alleviate the load applied onto the occupant, a method in which a predetermined tensile load of the seatbelt is held while predetermined feeding-out resistance or more is applied on the seatbelt immediately after the lock, and the seatbelt is fed out by a predetermined length in that state so as to absorb collision energy acting on the occupant (Energy Absorption; hereinafter referred to as “EA” as appropriate) has been known.
For example, in a retractor device described in JP, A, 2010-089528, an EA mechanism provided with a shaft member (torsion bar) is disclosed. That is, in this EA mechanism, one side end portion of a winding member is connected to a shaft member, and the other side end portion of the shaft member is locked at a collision so that the collision energy is absorbed by plastic deformation caused due to torsion of the shaft member.